3 * Linux INET6 implementation
5 * Based on net/dccp6/ipv6.c
7 * Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
15 #include <linux/module.h>
16 #include <linux/random.h>
17 #include <linux/xfrm.h>
19 #include <net/addrconf.h>
20 #include <net/inet_common.h>
21 #include <net/inet_hashtables.h>
22 #include <net/inet_sock.h>
23 #include <net/inet6_connection_sock.h>
24 #include <net/inet6_hashtables.h>
25 #include <net/ip6_route.h>
27 #include <net/protocol.h>
28 #include <net/transp_v6.h>
29 #include <net/ip6_checksum.h>
36 /* Socket used for sending RSTs and ACKs */
37 static struct socket *dccp_v6_ctl_socket;
39 static struct inet_connection_sock_af_ops dccp_ipv6_mapped;
40 static struct inet_connection_sock_af_ops dccp_ipv6_af_ops;
42 static int dccp_v6_get_port(struct sock *sk, unsigned short snum)
44 return inet_csk_get_port(&dccp_hashinfo, sk, snum,
45 inet6_csk_bind_conflict);
48 static void dccp_v6_hash(struct sock *sk)
50 if (sk->sk_state != DCCP_CLOSED) {
51 if (inet_csk(sk)->icsk_af_ops == &dccp_ipv6_mapped) {
56 __inet6_hash(&dccp_hashinfo, sk);
61 /* add pseudo-header to DCCP checksum stored in skb->csum */
62 static inline u16 dccp_v6_csum_finish(struct sk_buff *skb,
63 struct in6_addr *saddr,
64 struct in6_addr *daddr)
66 return csum_ipv6_magic(saddr, daddr, skb->len, IPPROTO_DCCP, skb->csum);
69 static inline void dccp_v6_send_check(struct sock *sk, int unused_value,
72 struct ipv6_pinfo *np = inet6_sk(sk);
73 struct dccp_hdr *dh = dccp_hdr(skb);
75 dccp_csum_outgoing(skb);
76 dh->dccph_checksum = dccp_v6_csum_finish(skb, &np->saddr, &np->daddr);
79 static inline __u32 dccp_v6_init_sequence(const struct sk_buff *skb)
81 return secure_tcpv6_sequence_number(skb->nh.ipv6h->daddr.s6_addr32,
82 skb->nh.ipv6h->saddr.s6_addr32,
83 dccp_hdr(skb)->dccph_dport,
84 dccp_hdr(skb)->dccph_sport );
87 static void dccp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
88 int type, int code, int offset, __be32 info)
90 struct ipv6hdr *hdr = (struct ipv6hdr *)skb->data;
91 const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data + offset);
92 struct ipv6_pinfo *np;
97 sk = inet6_lookup(&dccp_hashinfo, &hdr->daddr, dh->dccph_dport,
98 &hdr->saddr, dh->dccph_sport, inet6_iif(skb));
101 ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
105 if (sk->sk_state == DCCP_TIME_WAIT) {
106 inet_twsk_put(inet_twsk(sk));
111 if (sock_owned_by_user(sk))
112 NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);
114 if (sk->sk_state == DCCP_CLOSED)
119 if (type == ICMPV6_PKT_TOOBIG) {
120 struct dst_entry *dst = NULL;
122 if (sock_owned_by_user(sk))
124 if ((1 << sk->sk_state) & (DCCPF_LISTEN | DCCPF_CLOSED))
127 /* icmp should have updated the destination cache entry */
128 dst = __sk_dst_check(sk, np->dst_cookie);
130 struct inet_sock *inet = inet_sk(sk);
133 /* BUGGG_FUTURE: Again, it is not clear how
134 to handle rthdr case. Ignore this complexity
137 memset(&fl, 0, sizeof(fl));
138 fl.proto = IPPROTO_DCCP;
139 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
140 ipv6_addr_copy(&fl.fl6_src, &np->saddr);
141 fl.oif = sk->sk_bound_dev_if;
142 fl.fl_ip_dport = inet->dport;
143 fl.fl_ip_sport = inet->sport;
144 security_sk_classify_flow(sk, &fl);
146 err = ip6_dst_lookup(sk, &dst, &fl);
148 sk->sk_err_soft = -err;
152 err = xfrm_lookup(&dst, &fl, sk, 0);
154 sk->sk_err_soft = -err;
160 if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
161 dccp_sync_mss(sk, dst_mtu(dst));
162 } /* else let the usual retransmit timer handle it */
167 icmpv6_err_convert(type, code, &err);
169 seq = DCCP_SKB_CB(skb)->dccpd_seq;
170 /* Might be for an request_sock */
171 switch (sk->sk_state) {
172 struct request_sock *req, **prev;
174 if (sock_owned_by_user(sk))
177 req = inet6_csk_search_req(sk, &prev, dh->dccph_dport,
178 &hdr->daddr, &hdr->saddr,
184 * ICMPs are not backlogged, hence we cannot get an established
187 BUG_TRAP(req->sk == NULL);
189 if (seq != dccp_rsk(req)->dreq_iss) {
190 NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
194 inet_csk_reqsk_queue_drop(sk, req, prev);
197 case DCCP_REQUESTING:
198 case DCCP_RESPOND: /* Cannot happen.
199 It can, it SYNs are crossed. --ANK */
200 if (!sock_owned_by_user(sk)) {
201 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
204 * Wake people up to see the error
205 * (see connect in sock.c)
207 sk->sk_error_report(sk);
210 sk->sk_err_soft = err;
214 if (!sock_owned_by_user(sk) && np->recverr) {
216 sk->sk_error_report(sk);
218 sk->sk_err_soft = err;
226 static int dccp_v6_send_response(struct sock *sk, struct request_sock *req,
227 struct dst_entry *dst)
229 struct inet6_request_sock *ireq6 = inet6_rsk(req);
230 struct ipv6_pinfo *np = inet6_sk(sk);
232 struct ipv6_txoptions *opt = NULL;
233 struct in6_addr *final_p = NULL, final;
237 memset(&fl, 0, sizeof(fl));
238 fl.proto = IPPROTO_DCCP;
239 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
240 ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
241 fl.fl6_flowlabel = 0;
243 fl.fl_ip_dport = inet_rsk(req)->rmt_port;
244 fl.fl_ip_sport = inet_sk(sk)->sport;
245 security_req_classify_flow(req, &fl);
250 np->rxopt.bits.osrcrt == 2 &&
252 struct sk_buff *pktopts = ireq6->pktopts;
253 struct inet6_skb_parm *rxopt = IP6CB(pktopts);
256 opt = ipv6_invert_rthdr(sk,
257 (struct ipv6_rt_hdr *)(pktopts->nh.raw +
261 if (opt != NULL && opt->srcrt != NULL) {
262 const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt;
264 ipv6_addr_copy(&final, &fl.fl6_dst);
265 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
269 err = ip6_dst_lookup(sk, &dst, &fl);
274 ipv6_addr_copy(&fl.fl6_dst, final_p);
276 err = xfrm_lookup(&dst, &fl, sk, 0);
281 skb = dccp_make_response(sk, dst, req);
283 struct dccp_hdr *dh = dccp_hdr(skb);
285 dh->dccph_checksum = dccp_v6_csum_finish(skb,
288 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
289 err = ip6_xmit(sk, skb, &fl, opt, 0);
290 if (err == NET_XMIT_CN)
295 if (opt != NULL && opt != np->opt)
296 sock_kfree_s(sk, opt, opt->tot_len);
301 static void dccp_v6_reqsk_destructor(struct request_sock *req)
303 if (inet6_rsk(req)->pktopts != NULL)
304 kfree_skb(inet6_rsk(req)->pktopts);
307 static void dccp_v6_ctl_send_reset(struct sk_buff *rxskb)
309 struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
310 const u32 dccp_hdr_reset_len = sizeof(struct dccp_hdr) +
311 sizeof(struct dccp_hdr_ext) +
312 sizeof(struct dccp_hdr_reset);
317 if (rxdh->dccph_type == DCCP_PKT_RESET)
320 if (!ipv6_unicast_destination(rxskb))
323 skb = alloc_skb(dccp_v6_ctl_socket->sk->sk_prot->max_header,
328 skb_reserve(skb, dccp_v6_ctl_socket->sk->sk_prot->max_header);
330 dh = dccp_zeroed_hdr(skb, dccp_hdr_reset_len);
332 /* Swap the send and the receive. */
333 dh->dccph_type = DCCP_PKT_RESET;
334 dh->dccph_sport = rxdh->dccph_dport;
335 dh->dccph_dport = rxdh->dccph_sport;
336 dh->dccph_doff = dccp_hdr_reset_len / 4;
338 dccp_hdr_reset(skb)->dccph_reset_code =
339 DCCP_SKB_CB(rxskb)->dccpd_reset_code;
341 /* See "8.3.1. Abnormal Termination" in RFC 4340 */
343 if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
344 dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1);
346 dccp_hdr_set_seq(dh, seqno);
347 dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
348 DCCP_SKB_CB(rxskb)->dccpd_seq);
350 dccp_csum_outgoing(skb);
351 dh->dccph_checksum = dccp_v6_csum_finish(skb, &rxskb->nh.ipv6h->saddr,
352 &rxskb->nh.ipv6h->daddr);
354 memset(&fl, 0, sizeof(fl));
355 ipv6_addr_copy(&fl.fl6_dst, &rxskb->nh.ipv6h->saddr);
356 ipv6_addr_copy(&fl.fl6_src, &rxskb->nh.ipv6h->daddr);
358 fl.proto = IPPROTO_DCCP;
359 fl.oif = inet6_iif(rxskb);
360 fl.fl_ip_dport = dh->dccph_dport;
361 fl.fl_ip_sport = dh->dccph_sport;
362 security_skb_classify_flow(rxskb, &fl);
364 /* sk = NULL, but it is safe for now. RST socket required. */
365 if (!ip6_dst_lookup(NULL, &skb->dst, &fl)) {
366 if (xfrm_lookup(&skb->dst, &fl, NULL, 0) >= 0) {
367 ip6_xmit(dccp_v6_ctl_socket->sk, skb, &fl, NULL, 0);
368 DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
369 DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
377 static struct request_sock_ops dccp6_request_sock_ops = {
379 .obj_size = sizeof(struct dccp6_request_sock),
380 .rtx_syn_ack = dccp_v6_send_response,
381 .send_ack = dccp_reqsk_send_ack,
382 .destructor = dccp_v6_reqsk_destructor,
383 .send_reset = dccp_v6_ctl_send_reset,
386 static struct sock *dccp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
388 const struct dccp_hdr *dh = dccp_hdr(skb);
389 const struct ipv6hdr *iph = skb->nh.ipv6h;
391 struct request_sock **prev;
392 /* Find possible connection requests. */
393 struct request_sock *req = inet6_csk_search_req(sk, &prev,
399 return dccp_check_req(sk, skb, req, prev);
401 nsk = __inet6_lookup_established(&dccp_hashinfo,
402 &iph->saddr, dh->dccph_sport,
403 &iph->daddr, ntohs(dh->dccph_dport),
406 if (nsk->sk_state != DCCP_TIME_WAIT) {
410 inet_twsk_put(inet_twsk(nsk));
417 static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
419 struct request_sock *req;
420 struct dccp_request_sock *dreq;
421 struct inet6_request_sock *ireq6;
422 struct ipv6_pinfo *np = inet6_sk(sk);
423 const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
424 struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
425 __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY;
427 if (skb->protocol == htons(ETH_P_IP))
428 return dccp_v4_conn_request(sk, skb);
430 if (!ipv6_unicast_destination(skb))
433 if (dccp_bad_service_code(sk, service)) {
434 reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
438 * There are no SYN attacks on IPv6, yet...
440 if (inet_csk_reqsk_queue_is_full(sk))
443 if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
446 req = inet6_reqsk_alloc(&dccp6_request_sock_ops);
450 if (dccp_parse_options(sk, skb))
453 dccp_reqsk_init(req, skb);
455 if (security_inet_conn_request(sk, skb, req))
458 ireq6 = inet6_rsk(req);
459 ipv6_addr_copy(&ireq6->rmt_addr, &skb->nh.ipv6h->saddr);
460 ipv6_addr_copy(&ireq6->loc_addr, &skb->nh.ipv6h->daddr);
461 ireq6->pktopts = NULL;
463 if (ipv6_opt_accepted(sk, skb) ||
464 np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
465 np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
466 atomic_inc(&skb->users);
467 ireq6->pktopts = skb;
469 ireq6->iif = sk->sk_bound_dev_if;
471 /* So that link locals have meaning */
472 if (!sk->sk_bound_dev_if &&
473 ipv6_addr_type(&ireq6->rmt_addr) & IPV6_ADDR_LINKLOCAL)
474 ireq6->iif = inet6_iif(skb);
477 * Step 3: Process LISTEN state
479 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
481 * In fact we defer setting S.GSR, S.SWL, S.SWH to
482 * dccp_create_openreq_child.
484 dreq = dccp_rsk(req);
485 dreq->dreq_isr = dcb->dccpd_seq;
486 dreq->dreq_iss = dccp_v6_init_sequence(skb);
487 dreq->dreq_service = service;
489 if (dccp_v6_send_response(sk, req, NULL))
492 inet6_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
498 DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
499 dcb->dccpd_reset_code = reset_code;
503 static struct sock *dccp_v6_request_recv_sock(struct sock *sk,
505 struct request_sock *req,
506 struct dst_entry *dst)
508 struct inet6_request_sock *ireq6 = inet6_rsk(req);
509 struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
510 struct inet_sock *newinet;
511 struct dccp_sock *newdp;
512 struct dccp6_sock *newdp6;
514 struct ipv6_txoptions *opt;
516 if (skb->protocol == htons(ETH_P_IP)) {
520 newsk = dccp_v4_request_recv_sock(sk, skb, req, dst);
524 newdp6 = (struct dccp6_sock *)newsk;
525 newdp = dccp_sk(newsk);
526 newinet = inet_sk(newsk);
527 newinet->pinet6 = &newdp6->inet6;
528 newnp = inet6_sk(newsk);
530 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
532 ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF),
535 ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF),
538 ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);
540 inet_csk(newsk)->icsk_af_ops = &dccp_ipv6_mapped;
541 newsk->sk_backlog_rcv = dccp_v4_do_rcv;
542 newnp->pktoptions = NULL;
544 newnp->mcast_oif = inet6_iif(skb);
545 newnp->mcast_hops = skb->nh.ipv6h->hop_limit;
548 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
549 * here, dccp_create_openreq_child now does this for us, see the comment in
550 * that function for the gory details. -acme
553 /* It is tricky place. Until this moment IPv4 tcp
554 worked with IPv6 icsk.icsk_af_ops.
557 dccp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
564 if (sk_acceptq_is_full(sk))
567 if (np->rxopt.bits.osrcrt == 2 && opt == NULL && ireq6->pktopts) {
568 const struct inet6_skb_parm *rxopt = IP6CB(ireq6->pktopts);
571 opt = ipv6_invert_rthdr(sk,
572 (struct ipv6_rt_hdr *)(ireq6->pktopts->nh.raw +
577 struct in6_addr *final_p = NULL, final;
580 memset(&fl, 0, sizeof(fl));
581 fl.proto = IPPROTO_DCCP;
582 ipv6_addr_copy(&fl.fl6_dst, &ireq6->rmt_addr);
583 if (opt != NULL && opt->srcrt != NULL) {
584 const struct rt0_hdr *rt0 = (struct rt0_hdr *)opt->srcrt;
586 ipv6_addr_copy(&final, &fl.fl6_dst);
587 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
590 ipv6_addr_copy(&fl.fl6_src, &ireq6->loc_addr);
591 fl.oif = sk->sk_bound_dev_if;
592 fl.fl_ip_dport = inet_rsk(req)->rmt_port;
593 fl.fl_ip_sport = inet_sk(sk)->sport;
594 security_sk_classify_flow(sk, &fl);
596 if (ip6_dst_lookup(sk, &dst, &fl))
600 ipv6_addr_copy(&fl.fl6_dst, final_p);
602 if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0)
606 newsk = dccp_create_openreq_child(sk, req, skb);
611 * No need to charge this sock to the relevant IPv6 refcnt debug socks
612 * count here, dccp_create_openreq_child now does this for us, see the
613 * comment in that function for the gory details. -acme
616 __ip6_dst_store(newsk, dst, NULL, NULL);
617 newsk->sk_route_caps = dst->dev->features & ~(NETIF_F_IP_CSUM |
619 newdp6 = (struct dccp6_sock *)newsk;
620 newinet = inet_sk(newsk);
621 newinet->pinet6 = &newdp6->inet6;
622 newdp = dccp_sk(newsk);
623 newnp = inet6_sk(newsk);
625 memcpy(newnp, np, sizeof(struct ipv6_pinfo));
627 ipv6_addr_copy(&newnp->daddr, &ireq6->rmt_addr);
628 ipv6_addr_copy(&newnp->saddr, &ireq6->loc_addr);
629 ipv6_addr_copy(&newnp->rcv_saddr, &ireq6->loc_addr);
630 newsk->sk_bound_dev_if = ireq6->iif;
632 /* Now IPv6 options...
634 First: no IPv4 options.
639 newnp->rxopt.all = np->rxopt.all;
641 /* Clone pktoptions received with SYN */
642 newnp->pktoptions = NULL;
643 if (ireq6->pktopts != NULL) {
644 newnp->pktoptions = skb_clone(ireq6->pktopts, GFP_ATOMIC);
645 kfree_skb(ireq6->pktopts);
646 ireq6->pktopts = NULL;
647 if (newnp->pktoptions)
648 skb_set_owner_r(newnp->pktoptions, newsk);
651 newnp->mcast_oif = inet6_iif(skb);
652 newnp->mcast_hops = skb->nh.ipv6h->hop_limit;
655 * Clone native IPv6 options from listening socket (if any)
657 * Yes, keeping reference count would be much more clever, but we make
658 * one more one thing there: reattach optmem to newsk.
661 newnp->opt = ipv6_dup_options(newsk, opt);
663 sock_kfree_s(sk, opt, opt->tot_len);
666 inet_csk(newsk)->icsk_ext_hdr_len = 0;
667 if (newnp->opt != NULL)
668 inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
669 newnp->opt->opt_flen);
671 dccp_sync_mss(newsk, dst_mtu(dst));
673 newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6;
675 __inet6_hash(&dccp_hashinfo, newsk);
676 inet_inherit_port(&dccp_hashinfo, sk, newsk);
681 NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS);
683 NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS);
684 if (opt != NULL && opt != np->opt)
685 sock_kfree_s(sk, opt, opt->tot_len);
690 /* The socket must have it's spinlock held when we get
693 * We have a potential double-lock case here, so even when
694 * doing backlog processing we use the BH locking scheme.
695 * This is because we cannot sleep with the original spinlock
698 static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
700 struct ipv6_pinfo *np = inet6_sk(sk);
701 struct sk_buff *opt_skb = NULL;
703 /* Imagine: socket is IPv6. IPv4 packet arrives,
704 goes to IPv4 receive handler and backlogged.
705 From backlog it always goes here. Kerboom...
706 Fortunately, dccp_rcv_established and rcv_established
707 handle them correctly, but it is not case with
708 dccp_v6_hnd_req and dccp_v6_ctl_send_reset(). --ANK
711 if (skb->protocol == htons(ETH_P_IP))
712 return dccp_v4_do_rcv(sk, skb);
714 if (sk_filter(sk, skb))
718 * socket locking is here for SMP purposes as backlog rcv is currently
719 * called with bh processing disabled.
722 /* Do Stevens' IPV6_PKTOPTIONS.
724 Yes, guys, it is the only place in our code, where we
725 may make it not affecting IPv4.
726 The rest of code is protocol independent,
727 and I do not like idea to uglify IPv4.
729 Actually, all the idea behind IPV6_PKTOPTIONS
730 looks not very well thought. For now we latch
731 options, received in the last packet, enqueued
732 by tcp. Feel free to propose better solution.
737 * FIXME: Add handling of IPV6_PKTOPTIONS skb. See the comments below
738 * (wrt ipv6_pktopions) and net/ipv6/tcp_ipv6.c for an example.
740 opt_skb = skb_clone(skb, GFP_ATOMIC);
742 if (sk->sk_state == DCCP_OPEN) { /* Fast path */
743 if (dccp_rcv_established(sk, skb, dccp_hdr(skb), skb->len))
746 /* XXX This is where we would goto ipv6_pktoptions. */
747 __kfree_skb(opt_skb);
753 * Step 3: Process LISTEN state
754 * If S.state == LISTEN,
755 * If P.type == Request or P contains a valid Init Cookie option,
756 * (* Must scan the packet's options to check for Init
757 * Cookies. Only Init Cookies are processed here,
758 * however; other options are processed in Step 8. This
759 * scan need only be performed if the endpoint uses Init
761 * (* Generate a new socket and switch to that socket *)
762 * Set S := new socket for this port pair
764 * Choose S.ISS (initial seqno) or set from Init Cookies
765 * Initialize S.GAR := S.ISS
766 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
767 * Continue with S.state == RESPOND
768 * (* A Response packet will be generated in Step 11 *)
770 * Generate Reset(No Connection) unless P.type == Reset
771 * Drop packet and return
773 * NOTE: the check for the packet types is done in
774 * dccp_rcv_state_process
776 if (sk->sk_state == DCCP_LISTEN) {
777 struct sock *nsk = dccp_v6_hnd_req(sk, skb);
782 * Queue it on the new socket if the new socket is active,
783 * otherwise we just shortcircuit this and continue with
787 if (dccp_child_process(sk, nsk, skb))
790 __kfree_skb(opt_skb);
795 if (dccp_rcv_state_process(sk, skb, dccp_hdr(skb), skb->len))
798 /* XXX This is where we would goto ipv6_pktoptions. */
799 __kfree_skb(opt_skb);
804 dccp_v6_ctl_send_reset(skb);
807 __kfree_skb(opt_skb);
812 static int dccp_v6_rcv(struct sk_buff **pskb)
814 const struct dccp_hdr *dh;
815 struct sk_buff *skb = *pskb;
819 /* Step 1: Check header basics */
821 if (dccp_invalid_packet(skb))
824 /* Step 1: If header checksum is incorrect, drop packet and return. */
825 if (dccp_v6_csum_finish(skb, &skb->nh.ipv6h->saddr,
826 &skb->nh.ipv6h->daddr)) {
827 LIMIT_NETDEBUG(KERN_WARNING
828 "%s: dropped packet with invalid checksum\n",
835 DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb);
836 DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
838 if (dccp_packet_without_ack(skb))
839 DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
841 DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
844 * Look up flow ID in table and get corresponding socket */
845 sk = __inet6_lookup(&dccp_hashinfo, &skb->nh.ipv6h->saddr,
847 &skb->nh.ipv6h->daddr, ntohs(dh->dccph_dport),
854 dccp_pr_debug("failed to look up flow ID in table and "
855 "get corresponding socket\n");
861 * ... or S.state == TIMEWAIT,
862 * Generate Reset(No Connection) unless P.type == Reset
863 * Drop packet and return
865 if (sk->sk_state == DCCP_TIME_WAIT) {
866 dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
867 inet_twsk_put(inet_twsk(sk));
872 * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
873 * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
874 * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
876 min_cov = dccp_sk(sk)->dccps_pcrlen;
877 if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
878 dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
879 dh->dccph_cscov, min_cov);
880 /* FIXME: send Data Dropped option (see also dccp_v4_rcv) */
881 goto discard_and_relse;
884 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
885 goto discard_and_relse;
887 return sk_receive_skb(sk, skb) ? -1 : 0;
890 if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
895 * Generate Reset(No Connection) unless P.type == Reset
896 * Drop packet and return
898 if (dh->dccph_type != DCCP_PKT_RESET) {
899 DCCP_SKB_CB(skb)->dccpd_reset_code =
900 DCCP_RESET_CODE_NO_CONNECTION;
901 dccp_v6_ctl_send_reset(skb);
913 static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
916 struct sockaddr_in6 *usin = (struct sockaddr_in6 *)uaddr;
917 struct inet_connection_sock *icsk = inet_csk(sk);
918 struct inet_sock *inet = inet_sk(sk);
919 struct ipv6_pinfo *np = inet6_sk(sk);
920 struct dccp_sock *dp = dccp_sk(sk);
921 struct in6_addr *saddr = NULL, *final_p = NULL, final;
923 struct dst_entry *dst;
927 dp->dccps_role = DCCP_ROLE_CLIENT;
929 if (addr_len < SIN6_LEN_RFC2133)
932 if (usin->sin6_family != AF_INET6)
933 return -EAFNOSUPPORT;
935 memset(&fl, 0, sizeof(fl));
938 fl.fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
939 IP6_ECN_flow_init(fl.fl6_flowlabel);
940 if (fl.fl6_flowlabel & IPV6_FLOWLABEL_MASK) {
941 struct ip6_flowlabel *flowlabel;
942 flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
943 if (flowlabel == NULL)
945 ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
946 fl6_sock_release(flowlabel);
950 * connect() to INADDR_ANY means loopback (BSD'ism).
952 if (ipv6_addr_any(&usin->sin6_addr))
953 usin->sin6_addr.s6_addr[15] = 1;
955 addr_type = ipv6_addr_type(&usin->sin6_addr);
957 if (addr_type & IPV6_ADDR_MULTICAST)
960 if (addr_type & IPV6_ADDR_LINKLOCAL) {
961 if (addr_len >= sizeof(struct sockaddr_in6) &&
962 usin->sin6_scope_id) {
963 /* If interface is set while binding, indices
966 if (sk->sk_bound_dev_if &&
967 sk->sk_bound_dev_if != usin->sin6_scope_id)
970 sk->sk_bound_dev_if = usin->sin6_scope_id;
973 /* Connect to link-local address requires an interface */
974 if (!sk->sk_bound_dev_if)
978 ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
979 np->flow_label = fl.fl6_flowlabel;
984 if (addr_type == IPV6_ADDR_MAPPED) {
985 u32 exthdrlen = icsk->icsk_ext_hdr_len;
986 struct sockaddr_in sin;
988 SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
990 if (__ipv6_only_sock(sk))
993 sin.sin_family = AF_INET;
994 sin.sin_port = usin->sin6_port;
995 sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
997 icsk->icsk_af_ops = &dccp_ipv6_mapped;
998 sk->sk_backlog_rcv = dccp_v4_do_rcv;
1000 err = dccp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
1002 icsk->icsk_ext_hdr_len = exthdrlen;
1003 icsk->icsk_af_ops = &dccp_ipv6_af_ops;
1004 sk->sk_backlog_rcv = dccp_v6_do_rcv;
1007 ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
1009 ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF),
1016 if (!ipv6_addr_any(&np->rcv_saddr))
1017 saddr = &np->rcv_saddr;
1019 fl.proto = IPPROTO_DCCP;
1020 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
1021 ipv6_addr_copy(&fl.fl6_src, saddr ? saddr : &np->saddr);
1022 fl.oif = sk->sk_bound_dev_if;
1023 fl.fl_ip_dport = usin->sin6_port;
1024 fl.fl_ip_sport = inet->sport;
1025 security_sk_classify_flow(sk, &fl);
1027 if (np->opt != NULL && np->opt->srcrt != NULL) {
1028 const struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
1030 ipv6_addr_copy(&final, &fl.fl6_dst);
1031 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
1035 err = ip6_dst_lookup(sk, &dst, &fl);
1040 ipv6_addr_copy(&fl.fl6_dst, final_p);
1042 err = xfrm_lookup(&dst, &fl, sk, 0);
1046 if (saddr == NULL) {
1047 saddr = &fl.fl6_src;
1048 ipv6_addr_copy(&np->rcv_saddr, saddr);
1051 /* set the source address */
1052 ipv6_addr_copy(&np->saddr, saddr);
1053 inet->rcv_saddr = LOOPBACK4_IPV6;
1055 __ip6_dst_store(sk, dst, NULL, NULL);
1057 icsk->icsk_ext_hdr_len = 0;
1058 if (np->opt != NULL)
1059 icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
1060 np->opt->opt_nflen);
1062 inet->dport = usin->sin6_port;
1064 dccp_set_state(sk, DCCP_REQUESTING);
1065 err = inet6_hash_connect(&dccp_death_row, sk);
1070 dp->dccps_gar = secure_dccp_v6_sequence_number(np->saddr.s6_addr32,
1071 np->daddr.s6_addr32,
1075 err = dccp_connect(sk);
1082 dccp_set_state(sk, DCCP_CLOSED);
1086 sk->sk_route_caps = 0;
1090 static struct inet_connection_sock_af_ops dccp_ipv6_af_ops = {
1091 .queue_xmit = inet6_csk_xmit,
1092 .send_check = dccp_v6_send_check,
1093 .rebuild_header = inet6_sk_rebuild_header,
1094 .conn_request = dccp_v6_conn_request,
1095 .syn_recv_sock = dccp_v6_request_recv_sock,
1096 .net_header_len = sizeof(struct ipv6hdr),
1097 .setsockopt = ipv6_setsockopt,
1098 .getsockopt = ipv6_getsockopt,
1099 .addr2sockaddr = inet6_csk_addr2sockaddr,
1100 .sockaddr_len = sizeof(struct sockaddr_in6),
1101 #ifdef CONFIG_COMPAT
1102 .compat_setsockopt = compat_ipv6_setsockopt,
1103 .compat_getsockopt = compat_ipv6_getsockopt,
1108 * DCCP over IPv4 via INET6 API
1110 static struct inet_connection_sock_af_ops dccp_ipv6_mapped = {
1111 .queue_xmit = ip_queue_xmit,
1112 .send_check = dccp_v4_send_check,
1113 .rebuild_header = inet_sk_rebuild_header,
1114 .conn_request = dccp_v6_conn_request,
1115 .syn_recv_sock = dccp_v6_request_recv_sock,
1116 .net_header_len = sizeof(struct iphdr),
1117 .setsockopt = ipv6_setsockopt,
1118 .getsockopt = ipv6_getsockopt,
1119 .addr2sockaddr = inet6_csk_addr2sockaddr,
1120 .sockaddr_len = sizeof(struct sockaddr_in6),
1121 #ifdef CONFIG_COMPAT
1122 .compat_setsockopt = compat_ipv6_setsockopt,
1123 .compat_getsockopt = compat_ipv6_getsockopt,
1127 /* NOTE: A lot of things set to zero explicitly by call to
1128 * sk_alloc() so need not be done here.
1130 static int dccp_v6_init_sock(struct sock *sk)
1132 static __u8 dccp_v6_ctl_sock_initialized;
1133 int err = dccp_init_sock(sk, dccp_v6_ctl_sock_initialized);
1136 if (unlikely(!dccp_v6_ctl_sock_initialized))
1137 dccp_v6_ctl_sock_initialized = 1;
1138 inet_csk(sk)->icsk_af_ops = &dccp_ipv6_af_ops;
1144 static int dccp_v6_destroy_sock(struct sock *sk)
1146 dccp_destroy_sock(sk);
1147 return inet6_destroy_sock(sk);
1150 static struct timewait_sock_ops dccp6_timewait_sock_ops = {
1151 .twsk_obj_size = sizeof(struct dccp6_timewait_sock),
1154 static struct proto dccp_v6_prot = {
1156 .owner = THIS_MODULE,
1157 .close = dccp_close,
1158 .connect = dccp_v6_connect,
1159 .disconnect = dccp_disconnect,
1160 .ioctl = dccp_ioctl,
1161 .init = dccp_v6_init_sock,
1162 .setsockopt = dccp_setsockopt,
1163 .getsockopt = dccp_getsockopt,
1164 .sendmsg = dccp_sendmsg,
1165 .recvmsg = dccp_recvmsg,
1166 .backlog_rcv = dccp_v6_do_rcv,
1167 .hash = dccp_v6_hash,
1168 .unhash = dccp_unhash,
1169 .accept = inet_csk_accept,
1170 .get_port = dccp_v6_get_port,
1171 .shutdown = dccp_shutdown,
1172 .destroy = dccp_v6_destroy_sock,
1173 .orphan_count = &dccp_orphan_count,
1174 .max_header = MAX_DCCP_HEADER,
1175 .obj_size = sizeof(struct dccp6_sock),
1176 .rsk_prot = &dccp6_request_sock_ops,
1177 .twsk_prot = &dccp6_timewait_sock_ops,
1178 #ifdef CONFIG_COMPAT
1179 .compat_setsockopt = compat_dccp_setsockopt,
1180 .compat_getsockopt = compat_dccp_getsockopt,
1184 static struct inet6_protocol dccp_v6_protocol = {
1185 .handler = dccp_v6_rcv,
1186 .err_handler = dccp_v6_err,
1187 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL,
1190 static struct proto_ops inet6_dccp_ops = {
1192 .owner = THIS_MODULE,
1193 .release = inet6_release,
1195 .connect = inet_stream_connect,
1196 .socketpair = sock_no_socketpair,
1197 .accept = inet_accept,
1198 .getname = inet6_getname,
1200 .ioctl = inet6_ioctl,
1201 .listen = inet_dccp_listen,
1202 .shutdown = inet_shutdown,
1203 .setsockopt = sock_common_setsockopt,
1204 .getsockopt = sock_common_getsockopt,
1205 .sendmsg = inet_sendmsg,
1206 .recvmsg = sock_common_recvmsg,
1207 .mmap = sock_no_mmap,
1208 .sendpage = sock_no_sendpage,
1209 #ifdef CONFIG_COMPAT
1210 .compat_setsockopt = compat_sock_common_setsockopt,
1211 .compat_getsockopt = compat_sock_common_getsockopt,
1215 static struct inet_protosw dccp_v6_protosw = {
1217 .protocol = IPPROTO_DCCP,
1218 .prot = &dccp_v6_prot,
1219 .ops = &inet6_dccp_ops,
1221 .flags = INET_PROTOSW_ICSK,
1224 static int __init dccp_v6_init(void)
1226 int err = proto_register(&dccp_v6_prot, 1);
1231 err = inet6_add_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1233 goto out_unregister_proto;
1235 inet6_register_protosw(&dccp_v6_protosw);
1237 err = inet_csk_ctl_sock_create(&dccp_v6_ctl_socket, PF_INET6,
1238 SOCK_DCCP, IPPROTO_DCCP);
1240 goto out_unregister_protosw;
1243 out_unregister_protosw:
1244 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1245 inet6_unregister_protosw(&dccp_v6_protosw);
1246 out_unregister_proto:
1247 proto_unregister(&dccp_v6_prot);
1251 static void __exit dccp_v6_exit(void)
1253 inet6_del_protocol(&dccp_v6_protocol, IPPROTO_DCCP);
1254 inet6_unregister_protosw(&dccp_v6_protosw);
1255 proto_unregister(&dccp_v6_prot);
1258 module_init(dccp_v6_init);
1259 module_exit(dccp_v6_exit);
1262 * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
1263 * values directly, Also cover the case where the protocol is not specified,
1264 * i.e. net-pf-PF_INET6-proto-0-type-SOCK_DCCP
1266 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-33-type-6");
1267 MODULE_ALIAS("net-pf-" __stringify(PF_INET6) "-proto-0-type-6");
1268 MODULE_LICENSE("GPL");
1269 MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
1270 MODULE_DESCRIPTION("DCCPv6 - Datagram Congestion Controlled Protocol");